1. Technical Field
This document relates generally to the field of communications, and in particular toward processing encoded messages such as e-mail messages.
2. Description of the Related Art
In many known message exchange schemes, signatures, encryption, or both are commonly used to ensure the integrity and confidentiality of information being transferred from a sender to a recipient. In an e-mail system for example, the sender of an e-mail message could either sign the message, encrypt the message or both sign and encrypt the message. These actions may be performed using such standards as Secure Multipurpose Internet Mail Extensions (S/MIME), Pretty Good Privacy™ (PGP™), OpenPGP and many other secure e-mail standards.
In general, secure e-mail messages are relatively large. For example, S/MIME can increase the size of an e-mail message by a factor of ten (or more in some situations). This size augmentation presents difficulties, especially in the context of a resource-constrained device, such as a wireless mobile communication device. A resource-constrained device may also experience difficulty in handling a message wherein only a portion of the message has been transferred to the device. There is therefore a general need for a more efficient message handling approach.